I have heard about chickens laying two eggs a day. For the last couple of days I have gotten less than my normal amount of eggs. One moring there was goo in one of the nests so I suspect one had layed a shell-less egg. This morning when I checked my birds I checked the nest boxes there were no eggs. When I went out this (late) afternoon every one of my girls had laid an egg and there was one extra which means that one of my girls laid two eggs today.
That's cool! I think I have a double egg layer too, but I haven't proven it beyond a reasonable doubt yet.